Various Gd-complexes, Gd-EOB-DTPA, Gd-DTPA, Gd-DOTA-P were prepared and doped into hepatocyte suspensions. 1H NMR measurements were made on a GE 300MHz spectrometer, and the data submitted to continuous distribution analysis. Our study on water exchange in hepatocytes is based on the criteria: (1) the contrast agent has to be tissue specific and (2) that it must affect both intra- and extracellular relaxation.